It’s patently absurd, so why won’t it go away?

SIR John Forbes, the physician to Queen Victoria’s household, called it “an outrage to human reason.” Homeopathy’s claim is that you can take a substance of dubious properties, dilute it to the point where there are no molecules of the original substance left in the sample you have, and your sample will nevertheless have retained healing properties related to the original compound. There is no justification in all of science for this idea -- and yet there remains some slim evidence that homeopathy works.

The key word here is slim. But even the slimmest of evidence makes this scientifically tantalising. Are we missing something about the properties of water? Could there be ways to heal that involve ultra-dilution – possibly avoiding the nasty side-effects of certain drugs?

After months of investigation, my conclusion is a sour and muttered “probably not”. But even after a long journey into the heart of homeopathy, where I saw, among other things, a pharmacy whose shelves contained homeopathic remedies made from flapjack and musical harmonies, I still cannot be 100 per cent sure homeopathy is all bunkum. Part of the reason for that came as I sat in the botany library of the Natural History Museum reading a rigorous scientific analysis of the roots and efficacy of homeopathy, an analysis that might even be able to rescue homeopathy from the clutches of the cranks who currently run the show.